Essential genes are the set of genes thought to be critical for an organism's survival. This definition assumes the abundant availability of all relevant nutrients and the absence of environmental stress. Only a small portion of an organism's genes are essential. In bacteria, an estimated 250–400 genes are essential for Escherichia coli and Bacillus subtilis, which is less than 10% of their genes. Half of these genes are orthologs in both organisms and are largely involved in protein synthesis. In the budding yeast Saccharomyces cerevisiae the number of essential genes is slightly higher, at 1000 genes (~20% of their genes). Although the number is more difficult to measure in higher eukaryotes, mice and humans are estimated to have around 2000 essential genes (~10% of their genes).
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): How many genes are essential for Escherichia coli?
Ah, so.. 250–400

There are three classes of components for oxide glasses: network formers, intermediates, and modifiers. The network formers (silicon, boron, germanium) form a highly cross-linked network of chemical bonds. The intermediates (titanium, aluminium, zirconium, beryllium, magnesium, zinc) can act as both network formers and modifiers, according to the glass composition. The modifiers (calcium, lead, lithium, sodium, potassium) alter the network structure; they are usually present as ions, compensated by nearby non-bridging oxygen atoms, bound by one covalent bond to the glass network and holding one negative charge to compensate for the positive ion nearby. Some elements can play multiple roles; e.g. lead can act both as a network former (Pb4+ replacing Si4+), or as a modifier.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What type of component can both make and change ions? 
Ah, so.. unanswerable

In the judgment of political scientist Randall Ripley, since 1883 "the candidate for Speaker nominated by the minority party has clearly been the Minority Leader." However, this assertion is subject to dispute. On December 3, 1883, the House elected Democrat John G. Carlisle of Kentucky as Speaker. Republicans placed in nomination for the speakership J. Warren Keifer of Ohio, who was Speaker the previous Congress. Clearly, Keifer was not the Republicans' minority leader. He was a discredited leader in part because as Speaker he arbitrarily handed out "choice jobs to close relatives ... all at handsome salaries." Keifer received "the empty honor of the minority nomination. But with it came a sting -- for while this naturally involves the floor leadership, he was deserted by his [partisan] associates and his career as a national figure terminated ingloriously." Representative Thomas Reed, R-ME, who later became Speaker, assumed the de facto role of minority floor leader in Keifer's stead. "[A]lthough Keifer was the minority's candidate for Speaker, Reed became its acknowledged leader, and ever after, so long as he served in the House, remained the most conspicuous member of his party.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who assumed the role as Speaker after Randall Ripley?
Ah, so..
unanswerable