The concept useful in finding the answer to this item is ratio and proportion, the ratio of the height of your friend with the shadow casted should be proportional to the height of the rock with the length of the shadow it cast. That is,
5.5 ft / 18 ft = x ft/ 209.5 ft
The value of x from the equation above is 64 ft.
If 1/5 of the cards are hockey cards, there are 2 hockey cards. if he wants to double that amount, he would multiply it by 2, so 2•2=4. The fraction of hockey cards is now is 2/5.
The answer is C. To contradict something is to say or do the opposite of what is stated. If point S lies on plane PQR, it cannot not lie on plane PQR.