Express each of the following numbers in scientific notation with correct significant figures:
(a) 711.0
(b) 0.239
(c) 90743
(d) 134.2
(e) 0.05499
(f) 1.0
(g) 0.738592

The scientific notation normally appears as a decimal multiplied by 10 raised to a certain power. The scientific notation  for the following figures are shown on the right hand side;

a) 711.0 7.11 * 10^2

b)  0.239 2.39 * 10^-1

c) 90743 9.0743 * 10^4

d)  134.2 1.342 * 10^2

e)  0.05499 5.499 * 10^-2

f) 10000.0 1.00000 * 10^4

g) 0.000000738592 7.38592 * 10^-7

The manner in which these numbers are written is simple. Count the number of significant figures until you have something like x.y.

If we had to count ten places to the left before you got that, then the scientific notation is x.y * 10^-10. If i counted ten places to the left then i will write x.y * 10^10. The number of significant figures present must always be noted.

Learn more: link

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

nuclear fission produces elements that are heavier than helium.

the elements that are used in nuclear fission and their products are much heavier than helium.