Its sad when someone says FRIENDS NEEDED. Its sad they have no friends

How many types of rock can form from the rock cycle

The cretaceous period spanned the time interval between and 65 million years ago. 250 million 144 million 75 million 200 million

An adult inhales about 6.0×10−4 m3 of fresh air during a breath. only 20% of fresh air is oxygen. assume the pressure in the lungs is 1.0×105 paand the air is at a temperature of 300 k. how many oxygen molecules are in each breath? a. 1.4x10^23 b. 2.9x10^21 c. 4.9x10^-4 d. 2.9 x10^25