How many significant figures are there in the measurement (4.07×10^17m) Answer and I will give you brainiliest

please hlp

What do you think car designers do if the damage caused by a crash test is too severe?

With the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 1.90

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.