Docs cleanup

stdlib/public/Concurrency/ExecutorAssertions.swift

@@ -81,10 +81,10 @@ extension Actor {
   /// * In `-O` builds (the default for Xcode's Release configuration), stops
   ///   program execution.
   ///
-  /// - Note: This check is performed against the actor's serial executor,
-  ///   meaning that / if another actor uses the same serial executor--by using
+  /// - Note: Because this check is performed against the actor's serial executor,
+  ///   if another actor uses the same serial executor--by using
   ///   that actor's serial executor as its own ``Actor/unownedExecutor``--this
-  ///   check will succeed , as from a concurrency safety perspective, the
+  ///   check will succeed.  From a concurrency safety perspective, the
   ///   serial executor guarantees mutual exclusion of those two actors.
   ///
   /// - Parameters:

stdlib/public/Distributed/DistributedAssertions.swift

@@ -30,10 +30,10 @@ extension DistributedActor {
   /// * In `-O` builds (the default for Xcode's Release configuration), stops
   ///   program execution.
   ///
-  /// - Note: This check is performed against the actor's serial executor,
-  ///   meaning that / if another actor uses the same serial executor--by using
+  /// - Note: Because this check is performed against the actor's serial executor,
+  ///   if another actor uses the same serial executor--by using
   ///   that actor's serial executor as its own ``Actor/unownedExecutor``--this
-  ///   check will succeed , as from a concurrency safety perspective, the
+  ///   check will succeed.  From a concurrency safety perspective, the
   ///   serial executor guarantees mutual exclusion of those two actors.
   ///
   /// - Parameters:

stdlib/public/core/Duration.swift

@@ -251,7 +251,7 @@ extension Duration {
     return Duration(_high: highScaled + Int64(lowScaled.high), low: lowScaled.low)
   }
 
-  /// Construct a `Duration` given a number of seconds nanoseconds as a
+  /// Construct a `Duration` given a number of nanoseconds as a
   /// `Double` by converting the value into the closest attosecond scale value.
   ///
   ///       let d: Duration = .nanoseconds(382.9)

stdlib/public/core/FloatingPointTypes.swift.gyb

@@ -41,7 +41,7 @@ def Availability(bits):
 
 if Self == 'Float16':
     SelfDocComment = '''\
-/// A half-precision (16b), floating-point value type.
+/// A half-precision (16-bit), floating-point value type.
 ///
 /// On macOS, `Float16` is only available when targeting Apple silicon.
 /// On other supported platforms, `Float16` is available for all
@@ -50,11 +50,11 @@ if Self == 'Float16':
 /// arithmetic will be emulated by the swift compiler and runtime.'''
 elif Self == 'Float':
     SelfDocComment = '''\
-/// A single-precision, floating-point value type.'''
+/// A single-precision (32-bit), floating-point value type.'''
 
 elif Self == 'Double':
     SelfDocComment = '''\
-/// A double-precision, floating-point value type.'''
+/// A double-precision (64-bit), floating-point value type.'''
 
 elif Self == 'Float80':
     SelfDocComment = '''\