"Flight spoilers (2 -1/2/3/4/500; 4 -NG's) augment the ailerons and are
powered by hydraulic system A (inboard) & B (outboard). Spoilers will
continue to operate with speedbrake deployed.

Ground spoilers are also from hydraulic system A.

Only the outboard flight spoilers are powered by hydraulic sys B

On landing, if armed, all spoilers will deploy when the thrust levers
are at idle and any two wheels have spun up or right gear is
compressed. If not armed, the speedbrakes will deploy when reverse
thrust is selected."

While airborne you will only see flight spoiler. On landing flight
spoilers and ground spoilers deploy.

On an 737 NG -With the Speed Brake handle in the up position and on the
ground...
Gnd Spoilers #1,6,7, & 12 between 52 & 60 degrees
Flt. Spoilers # 2,3,4,5,8,9,10 &11 between 33 & 38 degrees

The photos show the spoilers not deployeed-SOP when configuring the
aircraft for emergency evacuation. Deployed spoilers would inhibit
overwing emergency evacuation.