Open the Ship.h file.

Add an instance variable called _juggler that is a pointer to SPJuggler, as shown in the following line of code:

SPJuggler *_juggler;

Declare a property called paused, which is of the type BOOL, as shown in the following line of code:

@property (nonatomic) BOOL paused;

Declare a method called advanceTime, as shown in the following line of code:

-(void) advanceTime:(double)seconds;

Switch to the Ship.m file.

Inside the initializer, set the paused property to NO using its instance variable, as shown in the following code:

_isShooting = NO;
_paused = NO;

SPTextureAtlas *atlas = (type == ShipPirate) ? [Assets textureAtlas:@"ship_pirate_small_cannon.xml"] : [Assets textureAtlas:@"ship_small_cannon.xml"];

Initialize the _juggler instance variable inside the initializer with the following line of code:

_juggler = [SPJuggler juggler];

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