It takes approximately 27 days
<span>2π/T = 2π/10 = π/5
y(x) = A sin (wx) = 0.75 sin (πx/5)
y(4) = 0.75 sin (4π/5) = 0.4408389392... ≈ 0.441</span><span>
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<span>C. A concave lens can only form a virtual image, because they are thinner in the middle and thicker around the edges.</span>
