When does the secondary sex characteristics appear?

Length of a school day in 1940 in America? One factor that drives atmospheric circulation is the movement of air from warm equatorial areas to cooler areas? What typeof elements may be found in lipids? What is an exothermic process? What river iS 34 south latitude 60 west longitude? How about this case 2NaOH plus Cl2? What elements would be assigned the highest electronegativity value? How can kenectic energy in a ball change back to potential energy? How much does a meteorologist get paid in Philly channel 6? Where do many of the plants on the phylum polypodiophyta live? What is the function of luncheon plate? When magma cools very slowly it will form very small crystals? What of a cell may be triggered to rupture resulting in the cell digesting itself? Why are not all farms organic? When the rate of repair lags behind the rate of mutation what is a possible fate of the cell? What organisms kingdom fungi include? Two major system of standard units use in measurement? Is there going to be an earthquake in Oregon? Which vascular tissue is responsible for carrying sugar down from the leaves to the rest of the plant? What are the bacterial diseases?