4. Use substitution to solve the following system of equations. d+ e-f= 3 e=f+ d + 1 f=2e-1

step-by-step explanation:

hunhgunyt7 in u uuuhiuteu

the answer would be d

straight away you can eliminate a and c because not all books contain a scientific skill because some may be fiction. c is also wrong because it saids that the only way children can learn is through books which is incorrect.

b is also wrong because reading can be a scientific skill but not always, therefore it is wrong which leaves you with d, the correct answer since it said that it can children learn.

hope this ! : 3

the answer is 13

step-by-step explanation:

5*5=25

12*12=144

25+144=169

169^2=13