Economics question! Help!?

[allicat]

I cannot figure out the answer to this question. If anyone could help me out, that would be great!

Explain whether each of the following events will increase, decrease, or have no effect on long-run aggregate supply.

a) The United States experiences a wave of immigration
b) Congress raises the minimum wage to $10 per hour
c) Intel invents a new and more powerful computer chip
d) A severe hurricane damages factories along the East Coast.

Any help would be greatly appreciated. Thanks!

[thenumberq2]

a) decreases LRAS (since the effects of immigration are only temporary before output falls back below it's natural rate)
b) increases LRAS (by increasing incentives for labourers to supply labour)
c) decreases LRAS (by increasing the ratio of capital to labour, reducing labour supply)
d) increases LRAS (opposite of c)