C is the answer i think but we dont see th graph
Answer:
2.375
Step-by-step explanation:
( 1.7 kg+2.1 kg+3 kg+ 2.7 kg)/4=2.375
In three dimensions, the cross product of two vectors is defined as shown below

Then, solving the determinant

In our case,

Where we used the formula for AxB to calculate ixj.
Finally,

Thus, (i+j)x(ixj)=i-j
There are 10 boys because half of 10 is 5 5+5 equals 10