Answer:
= -3i + (3/4+2i) - (9/3+3i)
= (3/4 - 9/3) + (-3 + 2 -3)i
= -9/4 -4i
The frequency is 1 /period = 1 / [ 2 pi ]
The answer is d is less than 6
7 out of 10 were carrying a backpack...and 3 out of 10 were not
that means 7/10 of the total students had backpacks and 3/10 of the total students did not
7/10 * 700 = 4900/10 = 490 had backpacks <==
3/10 * 700 = 2100/10 = 210 did not