An experiment was conducted to measure the effect of equal amounts of fertilizer on the growth of bean plants and corn plants. The results indicated that, although both seedlings benefited from the fertilizer, the bean plants benefited slightly more. Which graph best shows these results? A. X
B. W
C. Z
D. Y

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.