At least to continuous minutes of intense exercise must be used in order to improve cardiorespiratory endurance. A) 20 to 30

B) 5 to 10

C) 10 to 15

D) 50 to 60

i thinks its 20 - 30 because 50-60 would judt be entirely to much.

Explanation:

so we know the answer cannot be c because no insect or animal starts as an adult

the answer is a. a swimming larvae

because since they are sea animals they automatticaly have to know how to swim they cannot just sink to the bottom

sorry if this is the incorrect answer.

sex is when a male and female has intercourse (sexual)