25 of them.
there are 13 primes not 5.
There are only 2 primes in 80: 2 and 5.
There are 169 primes that are smaller than 1000.
There 25 primes less than 100: 2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97.
it is infinite
All pairs of two primes are coprime. There are fifteen primes under 50. So that means there are 105 unique pairs of "coprime primes", or more generally, pairs of primes, under 50.
One pair of twin primes between 135 and 145
There are infinitely many twin primes. One example is 5 and 7.
About 27.8 acres.
1100 grams = 1.1 kilograms.
1100 grams = 2.425 pounds
1100 yd = 1005.84 m