diff --git a/a1.py b/a1.py
index 651dfde..c05ca95 100644
--- a/a1.py
+++ b/a1.py
@@ -105,9 +105,13 @@ def calc_speed_at_outlet(water_height: float) -> float:
 def calc_new_water_height(old_water_height: float, reservoir_area: float, 
                     outlet_area: float, time_inc: float) -> tuple[float, float]:
     
+    water_mass_out = outlet_area * calc_speed_at_outlet(old_water_height) \
+        * time_inc * WATER_DENSITY
     
+    new_water_height = old_water_height - \
+        (water_mass_out / (reservoir_area * WATER_DENSITY))
 
-    return (0.0, 0.0)
+    return new_water_height, water_mass_out
 
 
 # See if I get what the task sheet wants
@@ -117,7 +121,7 @@ def sheet_tasks():
         (determine_power_used, (5e6, 250, 8, 85), 500.9191176470588),
         (determine_water_released, (300, 250, 8, 85), 2994495.4128440367),
         (determine_cost_to_pump, (300, 8, 0.02), 48),
-        (calc_speed_at_outlet, (30), 24.261079942986875),
+        (calc_speed_at_outlet, (30,), 24.261079942986875),
         (calc_new_water_height, (20, 40000, 1, 30), (19.985143183382704, 592567.1021442247)),
     )