Phrases such as "slow down! " "look up! " and "key point! " are all examples of:

These are examples of interjection. Interjection is a part of speech that denotes feeling and emotion. For instance, “that hurts!”, “cool!” and “beautiful!”. If noticed, these are accompanied by an exclamation point which highlight the authors point of emotion with respect to their statement. 

i would say the prokaryotic cells the prokaryotic cells are less complex, are usually found only in unicellular organisms and have more limited capabilities than eukaryotic cells.

9.9 years

a = p(1 + rt) . . account balance after time t at rate r starting with principal p

3000 = 2500(1 + 0.0202t) . . filling in the given numbers

1.2 = 1 + 0.0202t . . divide by 2500

0.2 = 0.0202t . . . subtract 1

0.2/0.0202 = t ≈ 9.901

it will take about 9.9 years for the account balance to reach $3000.