Why did Mansa Musa build a university in Timbuktu? "He wanted to build a school for his children.
He wanted to learned read.
He wanted scholars to come to Mali.

it would be d). more resources must be obtained to attain that combination of goods and services

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."

c

explanation: because you need to reduce the pollution on land,the exhaust fumes will stop,and stop it in water,the oil that is in the oceanharms the fish   sorry if you   have been waiting long