Which part of immun system is produced by bone marrow and circulates through body to destroy germs

Which multiplicative property is being illustrated below? (type commutative, associative, or identity) 5 × 2 × 4 = 2 × 5 × 4

Tanya has $42 to spend at the dolphin island store. tshirts sell for $7 each and a pair of sunglases sells for $6.tanya buys 3 tshirts. how many pairs of sunglases can she buys with the amount of money she has left

For which pair of functions is (gof)(a)=|a|-2?