A child has a toy balloon with a volume of 1.75 liters. The temperature of the balloon when it was filled was 21° C and the pressure was 1.00 atm. If the child
were to let go of the balloon and it rose 3 kilometers into the sky where the
pressure is 0.65 atm and the temperature is -10°C, what would the new volume
of the balloon be?

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.

answer seismograph;

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.