Hi! So when multiplying two numbers, the rule is that ti make the product negative you need one negative number and one positive or one negative number and as many positive numbers as you want. Really, the number of negative numbers needs to be odd because if there were 3 negative numbers like -2 x -2 x -2 then two of the -2's would make a positive 4 but then you have another -2 making the product negative. So it wouldn't be A because there are 2 negative numbers. It wouldn't be B because there are also 2 negative numbers It wouldn't be C because there are no negative numbers. It WOULD be D because there are 3 negative numbers so the product will come out to be negative.
Explanation: The 4 meter pole casts a shadow of 5 meters. The towers unknown height casts a shadow of 40 meters. Now isolate the shadows. 5 and 40. 40 divided by 5 is 8, so 4 times 8 is 32.
