Answer:
The answer is "789.03 and 806.16".
Step-by-step explanation:

For point a:
Calculating the value for

For point b:
Calculating the value of 
Answer:

Step-by-step explanation:
You need at least $90 dollars, so x will be bigger than or equal to that amount.
Your parents don't want to give you more than $150 dollars so x is smaller than or equal to that amount.
Just try to follow my description. When two persons are in the cabin, there is only 1 handshake. When a third person comes, he will have to handshake the two people who came before him. So, there will be 2 handshakes. When a fourth person comes, he would make 3 handshakes with the 3 people who came before him. When the fifth person comes, he would make 4 handshakes with the 4 people who came before him. So, you see there is a pattern. The number of handshakes is 1 less than the total number of people inside the cabin. So, if there are 14 people in the cabin, the last person to come in would have to make 13 handshakes with the 13 people who came in first. Obtaining the sum of all the handshakes starting from the 2 handshakes initially to the 13 handshakes, the sum would be
Total handshakes = 2+3+4+5+6+7+8+9+10+11+12+13
Total handshakes = 90
Therefore, there will be a total of 90 handshakes made within the cabin of 14 people.