diff --git a/lib/tree.rb b/lib/tree.rb
index 962b72e..c4d4663 100644
--- a/lib/tree.rb
+++ b/lib/tree.rb
@@ -1,38 +1,67 @@
 class NoApplesError < StandardError; end
 
 class Tree
-  attr_#fill_in :height, :age, :apples, :alive
+  attr_accessor :height, :age, :apples, :alive
 
   def initialize
+    self.height = 0
+    self.age = 0
+    self.apples = []
+    self.alive = true
   end
 
   def age!
+    self.age += 1
+    self.grow
+    self.add_apples
+
+    if self.age > 20
+      self.alive = false
+    end
+  end
+
+  def grow
+    if self.height < 20
+      self.height += 2
+    end
   end
 
   def add_apples
+    if self.age > 3
+      5.times { self.apples.push(Apple.new("red", rand(3.0..4.5).round(2))) }
+    end
   end
 
   def any_apples?
+    self.apples.length > 0
   end
 
   def pick_an_apple!
     raise NoApplesError, "This tree has no apples" unless self.any_apples?
+    apples.shift
   end
 
   def dead?
+    !self.alive
   end
 end
 
 class Fruit
+  attr_reader :has_seeds
+
   def initialize
-    has_seeds = true
+    @has_seeds = true
   end
 end
 
-class Apple <
-  attr_reader #what should go here 
+class Apple < Fruit
+  attr_reader :color, :diameter
 
   def initialize(color, diameter)
+    super()
+
+    @color = color
+    @diameter = diameter
   end
 end
 
@@ -61,7 +90,7 @@ def tree_data
       diameter_sum += apple.diameter
     end
 
-    avg_diameter = # It's up to you to calculate the average diameter for this harvest.
+    avg_diameter = (diameter_sum / basket.length).round(2)
 
     puts "Year #{tree.age} Report"
     puts "Tree height: #{tree.height} feet"
diff --git a/spec/tree_spec.rb b/spec/tree_spec.rb
index b4f44c6..a8df260 100644
--- a/spec/tree_spec.rb
+++ b/spec/tree_spec.rb
@@ -5,10 +5,66 @@
   it 'should be a Class' do
     expect(described_class.is_a? Class).to eq true
   end
+
+  let(:tree) { Tree.new }
+
+  it "is initialized as a young tree" do
+    expect(tree.age).to eq(0)
+  end
+
+  it "is alive" do
+    expect(tree.dead?).to be(false)
+  end
+
+  it "can age" do
+    tree.age!
+    expect(tree.age).to eq(1)
+  end
+
+  it "grows as it ages" do
+    tree.age!
+    expect(tree.height).to eq(2)
+  end
+
+  it "doesn't have apples for 3 years" do
+    3.times { tree.age! }
+    expect(tree.any_apples?).to be(false)
+  end
+
+  it "starts producing apples after 3 years" do
+    4.times { tree.age! }
+    expect(tree.any_apples?).to be(true)
+  end
+
+  it "can be harvested for apples" do
+    4.times { tree.age! }
+    expect(tree.pick_an_apple!).to be_instance_of(Apple)
+  end
+
+  it "dies after 20 years" do
+    21.times { tree.age! }
+    expect(tree.dead?).to be(true)
+  end
 end
 
 describe 'Fruit' do
+  it "has seeds" do
+    expect(Fruit.new.has_seeds).to be(true)
+  end
 end
 
 describe 'Apple' do
+  let(:apple) { Apple.new("red", 3.5)}
+
+  it "has a color" do
+    expect(apple.color).to eq("red")
+  end
+
+  it "has a diameter" do
+    expect(apple.diameter).to eq(3.5)
+  end
+
+  it "has seeds" do
+    expect(apple.has_seeds).to be(true)
+  end
 end