For the following situations, describe the contact and non contact forces that are involved. A. A book sitting on a shelf
B. A soccer player kicking a ball; the ball soaring through the air and landing on the ground
C. A hiker in the woods reading her compass to determine which direction to go
D. A child on a sled; first, the child is sitting at the top of the hill, waiting his turn; then, the child pushes off and slides down the hill, eventually coming to a ston

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

explanation:

venn diagram is pictorial representation with of circles showing the relation between two finite sets or things. the intersection part of two circles conveys the relation present in between those sets or things.

here in the venn diagram of sand and salt two circles represent sand and salt. but the area falling under the intersection of these circle represents the mixture of sand and salt.

so, in a venn diagram the mixture will be placed in a middle that is in between the intersection of two circles.

points

explanation: