The safest bet would be HD30. These small engines work hard and generate a lot of heat, so they need a slightly thicker oil than say a Honda civic engine. Most only take a small amount , so DONOT overfill.
Whenever you purchase a push mower you have to realize that it needs a higher grade oil. You should use a higher standard type of oil.
SAE 30 weight or SAE 10W-30 weight. I recommend you use 100% synthetic oil in your air-cooled engine.
That depends. Is a manual push mower with no motor, or a motorized one? Oil is usually rated by viscosity and I would use a single viscosity oil in a mower. Multiviscosity oils have modifiers to keep them fluid under cold conditions (in a car engine) but still thick when hot. In a mower a 30w oil would be ideal. Use the cheapest oil (in the long run): Amsoil synthetic.
Any kind you want.
sae30w
Usually, its SAE 30.
Hd 30w
If it's not a Honda, you can use HD 30 (single weight), 5W30, whatever you've got. If it's a Honda, they specify 10W30.
30W for summer
I use 5w-30
I have the exact same mower and I use mobil 1 5w30 and it seems to work
10w-30w is fine