I'LL GIVE BRAINLIEST PLEASE ANSWER ALL FOUR PLEASE

Step-by-step explanation:

1.) 700*0.42 = 294. Out of the 700 people at the concert, 294 are tennagers.

2.) 1.07*$450 = $481.50, including sales tax (final price)

3.) 120/(100%-85%) = 120/0.15 = 800. Original amount of water is 800 ml (Check by 800mL*0.15, which equals 120 mL)

4.) 100-35-45 = 20%

250*20% = 50; Out of the 250 sandwiches, Josh made 50 ham sandwiches.