Dave is walking from the back of a train to the front of the train at a rate of 6 kilometers per hour (km/hr). The train is traveling at a rate of 42 km/hr. What is
Dave's speed, relative to the ground?

Estimate the kinetic energy of mars with respect to the sun as the sum of two terms, that due to its daily rotation about its axis, and that due to its yearly revolution about the sun. (assume mars is a uniform sphere with mass = 6.4×10 to the power of 23 kg, radius = 3.4×10 to the power of 6 m, rotation period = 24.7 hours, orbital period = 686 days and is 2.3×10 to the power of 8 km from the sun.)

Three resistance 4,4 and 6 ohms are joined in the series.the total resistance will be

Row old is the rock laver2. if this sedimentary rock layer is truly the oldest one of marine origin, what do you think that tells usabout the formation of earth's oceans?