Suppose That the Weights of Vans Delivering Goods to Inner $\mu = 1510 \mathrm {~kg} ; \sigma = 620 \mathrm {~kg}$

Multiple Choice

Suppose that the weights of vans delivering goods to inner city shops are normally Distributed.If 70% of the vans weigh more than 1200 kg, and 80% weigh more than 1000 kg, What are the mean and standard deviation for the weights of vans serving the inner city
(round to tens) ?

A) $\mu = 1510 \mathrm {~kg} ; \sigma = 620 \mathrm {~kg}$
B) $\mu = 1530 \mathrm {~kg} ; \sigma = 630 \mathrm {~kg}$ ..
C) $\mu = 1550 \mathrm {~kg} ; \sigma = 640 \mathrm {~kg}$
D) $\mu = 1530 \mathrm {~kg} ; \sigma = 630 \mathrm {~kg}$ .
E) There is not enough information given to determine the mean and standard deviation.