Which statement best describes the process that forms a star? 1.Gravity condenses a cloud of dust and gas, initiating nuclear fusion.
2.A parent star explodes in a supernova, producing several daughter
stars.
3.A daughter star cleaves off of a parent star that has become too
massive to maintain equilibrium.
4.Nuclear fission splits atoms, releasing huge amounts of energy into
space.

We want to calculate the total metabolic heat generated by a singing canary taking into account heat transfer by radiation, convection and exhaling air. the air temperature is 20 oc, canary’s body internal and surface temperature is 33oc, external body surface convective heat transfer coefficient is 25.2 w/m2 .k, temperature difference between the inhaled and exhaled air is 4.3 oc, the ventilation rate is 0.74 cc of air per second, specific heat of air is 1.0066 kj/kg. k and density of air is 1.16 kg/m3 . assume the canary’s body to be a cylinder with 7 cm diameter and 9 cm length, and heat exchange is from the side as well as the top and bottom of cylinder. calculate 1) the net rate of heat lost by radiation, assuming heat gained by the bird through radiation from the surroundings is 11.5 w; 2) rate of heat transferred by convection to the surrounding air; 3) rate of heat transferred in the exhaling air without considering any internal evaporation; 4) total metabolic power.

Adistance-time graph indicates than an object moves 100 m in 4 s and then remains at rest for 6 s. what is the average speed of the object?

Physics pl 12)a body goes from p to q with a velocity of 10 m/s and comes back from q to p with a velocity of 20 m/s. what is the average velocity of the body during the entire trip? a)0 m/s b)13 m/s c)10 m/s d)15 m/s