Problem 1

3 5 7
4 2 1
5 3 9

Problem 2

for (int K = 7; K < 500; K +=7)
	cout << K << endl;
cout << endl;

Problem 3

double SphereVol(double R){
	return 4/3*pi*R*R*R;
}

int NumLetters(string s){
	int count = 0;
	for (int K = 0; K < s.length(); K++)
		if ((('a' <= s[K]) and (s[K] <= 'z')) or (('A' <= s[K]) and (s[K] <= 'Z')))
			count ++;
	return count;
}

3 11
6 110
11 1011

Problem 6

01001100_binary = 64 + 8 + 4 = 76_decimal
01110101_binary = 64 + 32 + 16 + 4 + 1= 117_decimal
00001111_binary = 8 + 4 + 2 + 1 = 15_decimal