Multiple Choice Correlation and Covariance

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Please show work, thank you!

Let Apple stock return be r_a and BP stock return r_b. If Cov(r_a, r_b) = 0.06, SD[r_a] = 0.5, and SD[r_b] = 0.4, then what is Corr(r_a, r_b)? 0.1 0.2 0.3 0.4 0.5 Let Apple stock return be r_a and BP stock return r_b. If Corr(r_a, r_b) = 0.7, SD[r_a] = 0.2, and SD[r_b] = 0.4, then what is Cov(r_a, r_b)? 0.016 0.026 0.036 0.046 0.056 Let Apple stock return be r_a and BP stock return r_b. If E[r_a times r_b] = 0.03, E[r_a] = 0.15, and E[r_b] = 0.10, then what is Cov(r_a, r_b)? 0.015 0.025 0.035 0.045 0.055