Omar wrote a hypothesis about batteries called dry cells. If more dry cells are connected end to end, a light bulb will work longer because there is more energy available. What are the variables in his hypothesis? The independent variable is the number of dry cells, and the dependent variable is the length of time the bulb works. The independent variable is the length of time the bulb works, and the dependent variable is the number of dry cells. The independent variable is the number of dry cells, and the dependent variable is the amount of energy available. The independent variable is the amount of energy available, and the dependent variable is the number of dry cells.

According to social exchange theory, altruistic behaviors benefit the individual who performs them.

Fft review: linspace, fs, fftshift, nfft 1. generate one second of a cosine of w,-10hz sampled at f, = 100hz and assign it to x. define a tt as your time axis 2. take 64 points fft. 3. as you remember, the dft (which the fft implements) computes n samples of s2t where k-0,1,2, n -1. plot the magnitude of this 64-points fft at range 0 to 63, what do you think of this graph? 4â·to get the x-axis into a hz-frequency form, plot this 64-points fft between-50 to 50 (the 100hz sampling rate) and have n-points between them. 5. according to your figure, what frequency is this cosine wave at? 6. remember that the fft is evaluating from 0 to 2ď€. we are used to viewing graphs from-ď€ to ď€. therefore, you need to shift your graph. 7. now according to your shifted graph. what frequency is this at? 8. note that the spikes have long drop-offs? try a 1024-point dft. note that the peak is closer to 10 and the drop-off is quicker. although, now sidelobes are an issue

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2