Answer:
k=20.
Explanation: First we find where f(x) has its local extrema: f'(x)=3x2−10x+3. The critical points are roots of the equation: 3x2−10x+3=0.
Answer is (d) P, Q , R
Any triangle has 3 vertices , after which its name is justified
So we solve for each
70% of 100=70
students who didn't buy lunch=100-70=30
some of the 70 left so that the students who bought lunch, are 60% of those who are left
we know that the students who didn't buy lunch didn't change number so therefor
100% of students left-60%=40%= students that didn't buy lunch=30 so
40%=30
20%=15
100%=75
there were 75 students lfet in the cafeteria
