Correct a spelling mistake

 In line25, it should be ‘installed’ instead of 'installl' :)

docs/qa.md

@@ -22,7 +22,7 @@ torch.cuda.init()
 print(torch.randn(1, device='cuda'))
 ```
 
-If you met an error, it is likely that your PyTorch build does not work with CUDA, e.g., it is installl from the official MacOS binary, or you have a GPU that is too old and not supported anymore. You may run the the code with CPU using `--gpu_ids -1`.
+If you met an error, it is likely that your PyTorch build does not work with CUDA, e.g., it is installed from the official MacOS binary, or you have a GPU that is too old and not supported anymore. You may run the the code with CPU using `--gpu_ids -1`.
 
 #### TypeError: Object of type 'Tensor' is not JSON serializable ([#258](https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix/issues/258))
 Similar errors: AttributeError: module 'torch' has no attribute 'device' ([#314](https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix/issues/314))