A paper airplane was thrown from the top of a tall building. The height of the paper airplane above the ground can be found using the function   y  =  −1.5x + 60 
where x is the time in seconds the airplane has been in the air.

 How many seconds did it take the paper airplane to reach the ground?

19.

step-by-step explanation:

you add the 9 in the tens column since it is a single digit and 9 plus zero is 9 so it is 19

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.

what shape is