I'll give best answer, stars, as many points as i can

a 2,460 kg truck traveling north with a speed of 130 km/hr runs into a car traveling in the same direction with a speed of 89 km/hr.
the mass of the car is 1,225 kg.
after the collision, the two move northward together as one mass.
what is the speed of the wreck?

a) 13.4 km/hr

b) 120 km/hr

c) 22.7 km/hr

Momentum is always conserves in a collision, so 2460*130 + 1225*89 = total momentum. After the collision, you can treat the two vehicles as one mass and divide momentum by mass to obtain velocity. 428825/3685 = 116.37 km/hr. Closest answer is B

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz