Answer:
V=I R
120= I × 20
I = 120÷20
I = 6 A
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Answer
He should've drawn the arrow starting from -15 pointing right to show how adding these two numbers would equal zero... hope this helped
Step-by-step explanation:
Answer:

Step-by-step explanation:
Let x = the current of the river
Then 21 + x = the speed going downstream (with the current)
a nd 21 - x = the speed going upstream (against the current)
Distance = speed × time
d = st
t = d/s
Time going downstream = time going upstream


Check:

OK